Shares of common stock acquired upon vesting of Restricted Stock Units (RSUs) granted June 8, 2011 pursuant to the CDTI Stock Incentive Plan.

Shares were sold to cover the reporting person's tax obligation in connection with the vesting of RSUs and conversion into shares of common stock.

The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $2.17 to $2.23, inclusive. The reporting person undertakes to provide CDTI, any security holder of CDTI or the staff of the Securities and Exchange Commission upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote to this Form 4.

Each RSU represents a contingent right to receive one share of CDTI common stock.

The RSU vests as to 1/3 on the seventh business day from June 8, 2011, the date of grant, and 1/3 each on the first and second anniversary of the date of grant. Issuance will occur on vest date. RSUs that have not vested at the time of the reporting person's termination of service, for any or no reason other than death, will be forfeited.